Contacting apparatus



April 4, 1950 G. JOHNSON ET A1.

CONTACTING APPARATUS 3 Sheets-Sheet 1 Filed March 2?-, 1946 Nm hw N April 4, '195D Filed March 27,' 1946 G. l.. JOHNSON ETAL coNTAcTING APPARATUS FUEL G50/PGE Jam/50N, JOHN HHPPEL mw JHM/ f5 w. MCA/EE A INVENTOR5 vATTORNEY April 4, 1950 G. JOHNSON ET AL 2,503,202

coNTAcTING APPARATUS Filed March 27, 1946 v v 3 SheetS-Sheet 3 .74ME5 M4 A//c/fEE INVENTORS NM/97K?? ATTORNEY Patented Apr. 4, 1 950 CONTACTIN G APPARATUS George L. Johnson, New York, John Happel, Brooklyn, and James W. McKee, New York, N. Y., assignors to Socony-Vacuum Oil Company, Incorporated, a corporation of New York Application March 27, 1946, Serial No. 657,593

3 Claims.

This invention relates to apparatus for the thermal cracking of hydrocarbons by contacting with a highly heated solid material. The apparatus of this invention is also useful for gas and solid contacting operations in general.

High yields of valuable unsaturated materials can be obtained by cracking hydrocarbons at high temperatures for relatively short periods of time. For example, high yields of ethylene are obtained by cracking crude oils and fractions thereof at temperatures on the order of 1500 F. to 1700 F. for reaction times of less than one second. Short time cracking of such materials as propane, ethane, etc., at temperatures on the order of 2300o F. gives high yields of acetylene. action times must be kept short in order to avoid extensive secondary condensation reactions and the processes vare advantageously conducted by passing the reactant fluid in direct contact with a highly heated granular solid to thereby rapidly raise the reactants to reaction temperature.

The present apparatus provides means for preheating, preferably with vaporization from the liquid state, of reactant iluids in contact with granular solids which have been cooled by rais-l ing such preheated reactant vapors to the desired reaction temperature. The invention is particularly advantageous in high temperature cracking of hydrocarbons in the presence of steam since it provides means for preheating water and hydrocarbon vapors, mixing the vapors and equalizing pressures thereof followed by introduction of the prepared reaction mixture to a high temperature contacting zone.

Further objects and advantages of the invention will be apparent from the specific forms shown in the annexed drawings, wherein Figure 1 is a flow sheet of apparatus for cracking of gas oil to ethylene in contact with a hot solid;

Figure 2 is a vertical section through the heater shown in Figure 1; Y C

Figure 3 is a horizontal section on line 3 3" of Figure2;and

Figure 4 is a vertical section through the reactor of Figure 1.

Referring particularly to Figure l, the scheme shown involves the use of two separate circulating systems for granularsolids. The reaction cycle includes a heater I Il for heating granular solids which are then passed to a reactor II in which they are contacted with hydrocarbon charge to heat the same to reaction temperature. vThe feed leg I2 for transfer of solids from heater IIJ to reactor I I is preferably provided with The re- Y products.

let temperature of reactor II is higher than that which can be tolerated by the elevator. Injection of water by fogrnozzles is well adapted to this purpose. If the water be injected at chamber I 5, the steam produced is exhausted as indicated. The water may be introduced to solids falling to the buckets at thebottom of the elevator, in which case, the elevator shaft also acts as an exhaust stack. Feed pipe I8 preferably includes a classier I9 for removal from the system of granular solids of a size smaller than that desired. Oil and water for the reaction are admitted to reactor I0 by lines 20 and 2l wherein they are heated to the desired temperature. If desired, the oil and water charge may be admitted in liquid phase to be vaporized in the lower part of the reactor. Alternatively, vaporization may be accomplished in any suitable manner prior to admission to the reactor. The reaction mixture from the top of reactor Il is promptly quenched to a reduced temperature, say 1200 F. by water admitted at 22 and is then transferred by line 23 to a solid quench chamber 24 wherein its temperature is further reduced, say to 575 F. and the vapors are then transferred by line 25 through heat exchanger 26 to a vapor separator 2l. The final cooling step (heat exchanger 2E) may be alternatively conducted by a second liquid quench as water or cold oil. The reaction mixture enters vapor separator 2l at a suitable low temperature such as100 F. and vapors are taken overhead by line 28 for separation of gaseous TheV liquid phase in separator 21 is transferred to a settling zone .(not shown) by line 29 where'inoil and water are-separated.' The separated Water maybe used foradmission 'tc the reactor 'at line 2j 'and 'as quench Water at lne`22 since any'contaminating depositsy in the .water so used are laid down onthe granular solid and later removed by combustion in heater It and air preheater 32. The oil maybe' recycled in whole or in parttothe reactor as'deSired.. Genand classifier 31 to a feed hopperf38.. Granular.'

solids from the feed hopper 38 are then transferred by feed leg 39 through steam sealing chainew ber 40 to the quencher.

Air for cooling granular solids in cooler 32l is supplied by blower 4I and heated air: is with:- drawn from the cooler by pipe 42. and'transferred" to the heater wherein it is usedit'oburn-fuelsup plied by line 43. A system of 'this general type' wherein the air from the coolerisfsuppl-ied to the:

heater is described and claimed in United States Patent 2,444,650y issued April 4, 1946..

The details and operation of the heater are seen by reference-to'Figures Zand-3; Essentially; the heater-comprises;aishell 41! having ftwo-tubesheetss 45; and; 46..' dividingstheisame' intot an'y upper' prei heating'. zone;` an intermediate". combustion andi high'.temperature-heating y zone andalowerfcomw bustion and high temperature `heating/zone.. The.- preheatingzone'is essentially setaup .to operateas two: successive preheating sections: but". flowA oi gases between :the two sections; ist not'.` ei`ciently. inhibited as' is .flow between the preheating: a'nd'fintermediate high temperature azonez-z and between" theatwohigh temperature zones.

In eaclnffthefl'iigh temperaturefrohesse:number of feedpipes 4Midependffrornl the tubefsheet'topro--Y vide pathsiof restricted? cross-section for. passage: of the granular solids. This'. largely inhibitswupewardfl'ow 'of gases andlcauses equal distribution .off flowingfsolidsacrossJ the heater: The feed tubes: 41@ also provide aniopen-space belowthe'tube' sheet; inrwhich are installedairxfeedheaders dzandiueh headers 49; Air a'ndfuel.` from:the-:headersnarei' supplied .to burners v50 .whichrnay lienomorei than. concentric pipes as shown. Thezburners7 50i provide. a flame which iswpreferablyy directed: onto: the surface ofthe' granular solids lyingt atan angle: belowtheopen lowerend of feed'tubesli'i. Corn-1 bustion is very efficient because :off the1cata1ytic. eiect of solid surfaces: and: high. temperature. productsV of combustion are. generated in directt contact with theegranularsolidss. The. productsv of combustion'in the rstzhigh temperaturezonez arexrernoved by the gas x collector: 5l' and. transe ferred by line52 to aigas distributor 53 inthepreheating zone. Similarly; the fprmiuctsxof"combusf` tionzin the lower: highitemperature zone.arere movedby collector. 5?!` andtransferred by line 55 to distributor 56;' Gras-collectorsl 51f and 58'in.thef preheating zone inducecountercurrent ow of the hot. productsV of combustion inrthefupper pre-- heating zoneY and: the; flue; gasesvv are 1 transferred. from theicollectorsf'- and 53T toga stack orseconofmiser;- byj linef-I 5.9. It.. is'. preferred tl'1a'.tf.the1v pre-Y. heating: zone; :bei spaced; afgconsiderablee distancef fromfinletvpipe .I latitheatoprofithesheatennnrder to'providea:bulk.v snpplyfofsolid'sin the-top? oftl're: heater. andlalsd tot.:inhibit.'.Yflowffof.gasesupwardly?` toi pipe l 8 by "theedeptlrofisolidsiinitheetop; Uni-a f oxrnlowrinzthe' bottcrn1-oiitheheater'isi induced by aipluraiitye oftflotw piates 6D, El; andvZ-flfiavingA orifices spacedinfsubstantially.thesmannershovm- The heater desc-ribedf hereinaboveandshowrr` in: Fguresiz and .3- isgdescribed; and claimed inzappli cation Serial'. Number;657,592 flledin the;` United States Patent Office on March 2'7, 1946;`

` As:showniniFigure4,` theA reactor.. H `is'enclosed fi l) by a shell 63 which is equipped with tube sheet B4 and 55. The space above the upper tube sheet 64 serves as a supply hopper from which high temperature granular solids are fed into a high temperature contacting Zone by feed tubes 66 depending from the tube sheet E4. This provides vapor sealing f zone whichvl inhibits; the'- loss of gases upwardly from thereactor` and the open space about the tubes 66 serves as a collection chamber from which vapors may be removed by pipe. 23.. and.. quenched with water by pipe 22 as noted'above in connection with Figure 1.

Asthexgranularsolids move downwardly from tubes 63" they rapidly heat reaction vapor to the desired reaction temperature and .are themselves cooled', reaching-tube sheet 65 at a substantially reduced temperature, say 1000 F. Vapors from the lower preheating zone are transferred through the tube sheet 65 by pipes 61 to inverted angles 58 which serve as vapor distributors. The granular solids Venterf'feed tubes. 69 which: function. in the same'mannerfas-tubes; 66 to.' prnvideza gas-.dise engaging 4spacefin `theanature 10i: av .plenumt cham'.- ber; Inthisregion preheatedoilan'dwaterrvapors from the lowerpartxof thereactorfare thoroughly mixedV and equalized` ase tor pressurefor.` feeding into theupper-'high temperature reaction Zone; In an intermedia'teiportion ofgtheipreheatin'gazone are a plurality of invertedtrouglis Illwhichserve to distribute;uidsp:Suppliedy by'pipes1 Til. In ai typical operation thezfiuid from' pipes:- 1l.' maybe? liquidv oilwhichA is vaporized. anda. preheated: by; contact with thezhotsolidsimoying'downwardly," through thepreheating Zone: Similar. distributors'- maand pipes-.13:'serveztofsupplywater-'tothe preheating zoneiniA either; vapor; or;v liquid I phase.- asi desired. Thewater:vr is: preferably introduced as., liquidsince'dirtyiwaterjcanibezusediin:thisimannerf thus avoiding the,- difficulties? of purifying.;v waterY to be'. used' in'. conventional; steam generators; Apertured flow controljplates 174, 15 and 'min the bottom of reactor M function in the ,saine-manner as plates 6D, 6I and 62 in heater-18. In an opera.- tionwhereliquid oil :and liquid watery are admittedto the reactor granularsolidsy maybe-withdrawnl from the bottom of the reactory at a temperature on the .ordenof 780 A typicaloperation involving-the temperaturesnoted above charges Michigangas oil in liquidy phasev andidirty water to provide steam-amountingzto about 50.4%, byyweight of the amount of. gas oil charge. A- space velocityof. 31.12 volumes of liquidv oil aty 60 li'.v per volume of reac-l tion space, i. e. abovetube sheet B5, is maintained using` a weight ratio'of 11.9.= partsV of granular solids to Lpart of'oil'ina beddepth of24 inches.- This gives' a-meaneffective temperature of 1440 F; ata contact timeof 0.29 second. Amongthe important products .are 28.1%,ethylene and 18.3%l C3 and C4 olens. The process also yields 5.5% depentanized motor;y gasoline. having.- an. octane number of 94.6 with 3 cc. of tetraethyhlead. The gasoline .is'ghighlyr aromaticfand' is also usefulA as y solvents and the like.

Weclaim: l

1. An improved vapor preheater and-.reactor comprisinga verticaL vesselhaving; a solid .materialinlet conduiti on: itszfupper.: endv and. a solidmaterial outlet conduiton itslower end, apar-- titionacross theupper portionof said .vesseland a below, thereby providing confined passages for solid flow between chambers and providing a continuous gas space below each partition and surrounding the conduits depending therefrom, a gas outlet conduit connected into said vessel ata level below the upper partition and above the lower ends of the conduits depending therefrom, a row of spaced, horizontally extending gas distributing troughs, open on bottom, positioned in said vessel shortly above the lower partition and substantially below the lower ends of the conduits depending from the upper partition, a plurality of tubes extending through said lower partition from the gas space therebelow and terminating under said troughs, a second row of horizontally extending distributor troughs within said vessel at a level spaced substantially below the lower ends of said conduits which depend from said lower partition, conduit means for supplying a fluid oil under said troughs, a third row of troughs positioned in the lower portion of said vessel below said last named row of troughs and separate conduit means yfor supplying water under said troughs.`

2. In a reactor for preparing a mixture of preheated vapors and contacting the mixture with a hot granular solid to raise the mixture to reaction temperature; a vertical shell, an inlet for granular solids at the top of said shell, an outlet for granular solids at the bottom of said shell, a tube sheet intermediate the ends of said shell, a plurality of tubes piercing said tube sheet and depending therefrom to form a plenum chamber below said tube sheet among said tubes, uid distributors in said shell below said plenum chamber, a plurality of spaced hood-like distributing bailles open on bottom positioned within said vessel shortly above said tube sheet, tubes extending through said tube sheet and terminating under said baiiies so as to communicate said plenum chamber with the underside of said hood-like baiiles, and a gas outlet conduit connected to said shell at a level substantially above said hoodlike baffles.

3. An improved vapor preheater and reactor 5 comprising: a vertical vessel having a solid material inlet conduit at its upper end and a solid material outlet conduit at its lower end, a partition across said vessel at a level intermediate its ends, dividing said vessel into two chambers, spaced conduits depending from said partition and terminating at a level a spaced distance therebelow but substantially above the lower' end of said vessel thereby providing a gas space below said partition and among said conduits, a plurality of spaced gas handling collecting hoods, open on bottom, positioned in said vessel above said partition, conduits communicating said gas space below said partitions with the undersides of said hoods, a gas flow conduit opening into said vessel at a level spaced above said hoods, a set of spaced hoods positioned in said vessel a spaced distance below the lower ends of said conduits which depend from said partition, conduit means communicating the undersides of said second named hoods with a location outside of said vessel, a second set off spaced hoods positioned in a lower section of said vessel below said rst named set and separate conduit means communicating the underside of said last named hoods -with a location outside said vessel.

GEORGE L. JOHNSON. JOHN HAPPEL. JAMES W. MCKEE.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Name Date Dunham Oct. 16, 1945 Number 2,386,846 

1. AN IMPROVED VAPOR PREHEATER AND REACTOR COMPRISING A VERTICAL VESSEL HAVING A SOLID MATERIAL INLET CONDUIT ON ITS UPPER END AND A SOLID MATERIAL OUTLET CONDUIT ON ITS LOWER END, A PARTITION ACROSS THE UPPER PORTION OF SAID VESSEL AND A LOWER PARTITION ACROSS SAID VESSEL AT AN INTERMEDIATE LEVEL ALONG ITS LENGTH, SAID PARTITION DIVIDING SAID VESSEL INTO THREE SUPERPOSED CHAMBERS, SPACED CONDUITS DEPENDING FROM EACH OF SAID PARTITIONS AND TERMINATING A SPACED DISTANCE THEREBELOW, THEREBY PROVIDING CONFINED PASSAGES FOR SOLID FLOW BETWEEN CHAMBERS AND PROVIDING A CONTINUOUS GAS SPACE BELOW EACH PARTITION AND SURROUNDING THE CONDUITS DEPENDING THEREFROM, A GAS OUTLET CONDUIT CONNECTED INTO SAID VESSEL AT A LEVEL BELOW THE UPPER PARTITION AND ABOVE THE LOWER ENDS OF THE CONDUITS DEPENDING THEREFROM, A ROW OF SPACED, HORIZONTALLY EXTENDING GAS DISTRIBUTING TROUGHS, OPEN ON BOTTOM, POSITIONED IN SAID VESSEL SHORTLY ABOVE THE LOWER PARTITION AND SUBSTANTIALLY BELOW THE LOWER ENDS OF THE CONDUITS DEPENDING FROM THE UPPER PARTITION, A PLURALITY OF TUBES EXTENDING THROUGH SAID LOWER PARTITION FROM THE GAS SPACE THEREBELOW AND TERMINATING UNDER SAID TROUGHS, A SECOND ROW OF HORIZONTALLY EXTENDING DISTRIBUTOR TROUGHS WITHIN SAID VESSEL AT A LEVEL SPACED SUBSTANTIALLY BELOW THE LOWER ENDS OF SAID CONDUITS WHICH DEPEND FROM SAID LOWER PARTITION, CONDUIT MEANS FOR SUPPLYING A FLUID OIL UNDER SAID TROUGHS, A THIRD ROW OF TROUGHS POSITIONED IN THE LOWER PORTION OF SAID VESSEL BELOW SAID LAST NAMED ROW OF TROUGHS AND SEPARATE CONDUIT MEANS FOR SUPPLYING WATER UNDER SAID TROUGHS. 